Valves for switching between a plurality of vacuum or pressure lines are finding increasing use in today's automobile and truck engines for operating controls relating to fuel economy and a wide range of accessory equipment, for example, exhaust gas recirculators and spark advance devices. Prior art valves have heretofore utilized separate fluid chambers in cooperation with flexible diaphragms which have proven to be complicated and expensive. Other prior art valves in use have used a single function ball. A major problem encountered in providing such devices has been that of fitting the device into available space around the engine block. This has particularly been a problem with valves which are actuated by a thermal sensor, where it has been necessary to provide a separate threaded access hole in the engine block for connections thereto as, for example, to the engine cooling system. A further disadvantage with prior art devices is that heretofore each valve required its own thermally responsive actuator and thus required a plurality of elements in the valve which has thus inherently increased the manufacturing cost.